<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <style>
        #d1 {
            height: 600px;
            padding: 50px;
            background-color: gray;
        }

        #d2 {
            height: 400px;
            background-color: orange;
            padding: 50px;
            font-size: 40px;
            color: yellow;
        }

        #d3 {
            height: 200px;
            background-color: green;
        }
    </style>
</head>
<body>

    <div id="d1">
        <div id="d2">
            <div id="d3">你好啊</div>
        </div>
    </div>
    
</body>
</html>